Leoric is an object-relational mapping for Node.js, which is heavily influenced by Active Record of Ruby on Rails. See the documentation for detail.
Assume the tables of posts, users, and comments were setup already. We may declare the models as classes by extending from the base class Bone
of Leoric. After the models are connect
ed to the database, the columns of the tables are mapped as attributes, the associations are setup, feel free to start querying.
const { Bone, connect } = require('leoric')
// define model
class Post extends Bone {
static describe() {
this.belongsTo('author', { Model: 'User' })
this.hasMany('comments')
}
}
async function() {
// connect models to database
await connect({ host: 'example.com', models: [Post], /* among other options */ })
// CRUD
await Post.create({ title: 'New Post' })
const post = await Post.findOne({ title: 'New Post' })
post.title = 'Untitled'
await post.save()
// or UPDATE directly
await Post.update({ title: 'Untitled' }, { title: 'New Post' })
// find with associations
const post = await Post.findOne({ title: 'New Post' }).with('comments')
console.log(post.comments) // => [ Comment { id, content }, ... ]
}
JavaScript | SQL |
---|---|
Post.create({ title: 'New Post' }) |
INSERT INTO posts (title) VALUES ('New Post') |
Post.all |
SELECT * FROM posts |
Post.find({ title: 'New Post' }) |
SELECT * FROM posts WHERE title = 'New Post' |
Post.find(42) |
SELECT * FROM posts WHERE id = 42 |
Post.order('title') |
SELECT * FROM posts ORDER BY title |
Post.order('title', 'desc') |
SELECT * FROM posts ORDER BY title DESC |
Post.limit(20) |
SELECT * FROM posts LIMIT 0, 20 |
Post.update({ id: 42 }, { title: 'Skeleton King' }) |
UPDATE posts SET title = 'Skeleton King' WHERE id = 42 |
Post.remove({ id: 42 }) |
DELETE FROM posts WHERE id = 42 |
A more detailed syntax table may be found at the documentation site.
Currently, Leoric doesn't provide a way to do database migrations. There are two popular approaches:
- A separated migration DSL and database metadata, like Active Record.
- A detailed enumeration of attributes and types in the models, like Django.
There is a third way, which is the very reason Leoric has yet to implement migrations, which is that the database can be designed through a third-party service. It can be an ER designer, a GUI software for MySQL, or a MySQL-compliant database in the cloud.
But I'm sure we'll get to that.